package pr01;

public class Triangle {
   
   private static final double PRECISION = 0.0000000001;
   
   private double side1;
   private double side2;
   private double angle;
   
   public Triangle(double side1, double angle, double side2) {
      this.side1 = side1;
      this.angle = angle;
      this.side2 = side2;
   }
   
   public double getSide1() {
      return side1;
   }
   
   public double getAngle() {
      return angle;
   }
   
   public double getSide2() {
      return side2;
   }
   
   public boolean isValid() {
      return side1 > 0 && side2 > 0 && angle > 0 && angle < 180;
   }
   
   public double getSide3() {
      if (!isValid())
         return 0;
      double convertedAngle = Math.toRadians(angle);
      double side3s = side1*side1 + side2*side2 - 
                 2*side1*side2*Math.cos(convertedAngle);
      return Math.sqrt(side3s);
   }
   
   public double getArea() {
      if (!isValid())
         return 0;
      double convertedAngle = Math.toRadians(angle);
      return side1 * side2 * Math.sin(convertedAngle)/2;
   }
   
   public boolean isEquilateral() {
      return isValid() && almostEqual(side1, side2) && (angle == 60.0);
   }
   
   public boolean isIsosceles() {
      if (!isValid())
         return false;
      if (almostEqual(side1, side2))
         return true;
      double side3 = getSide3();
      return almostEqual(side1, side3) || almostEqual(side2, side3);
   }
   
   private boolean almostEqual(double x, double y) {
      return Math.abs(x-y) < PRECISION;
   }
   
   public boolean isRight() {
      double thirdSide = getSide3();
      if (almostEqual(thirdSide*thirdSide, side1*side1 + side2*side2))
         return true;
      if (almostEqual(side1*side1,thirdSide*thirdSide + side2*side2))
         return true;
      if (almostEqual(side2*side2,thirdSide*thirdSide + side1*side1))
         return true;
      return false;
   }
   
   public String toString() {
      return "Triangle with sides "+side1+" and " + side2 +
      " and included angle "+angle + " degrees";
   }

}